1. Field of the Invention
The present invention relates generally to data and voice communications. More particularly, the present invention relates to network devices.
2. Background Art
Over the last several years, data transfer needs at all levels of network communication have grown dramatically. The growing demand for high data transfer capabilities in even PANs (personal area networks), fueled by ever increasing consumer desire for and reliance on electronic media access, has resulted in data transfer rate requirements for routine communications that would have been reserved for specialized communication needs in the recent past. Consequently, 10 GbE (10 gigabit Ethernet) speeds in use almost exclusively in WANs (wide area networks) and MANs (municipal area networks) only a short time ago are now used in localized datacenters as well.
The transition to 10 GbE in the datacenter or LAN (local area network) setting presents distinct challenges associated with the number of interconnects required, the highly variable length of those interconnects, and the extent to which the cabling providing those interconnects must withstand physical deformations through twisting and bending. Fiber optic cables, which have served as the backbone of 10 GbE over wider network configurations may be suboptimal choices for high speed LAN communications due to their cost and relative fragility. Copper cables, on the other hand, which have served as a staple physical medium in the lower speed 1 GbE LAN setting, consume large amounts of power at 10 GbE, restricting port density. An additional concern for 10 GbE over copper cables is latency, which can be as much as an order of magnitude greater than for optical cables.
One conventional approach to supporting 10 GbE communication in LANs is an optical cable solution, shown in FIG. 1. As seen there, networking system 100 includes communication system 108 having connection port 106, in communication with a remote communication system (not shown) through optical cable 102 having connection plug 104. In a typical optical cable solution for 10 GbE, connection port 106 may be an SFP+(small form-factor pluggable plus) module, for example, and connection plug 104 may be an LC (Lucent Connector) designed for use with an SFP+ module. In this conventional solution, connection port 106 is in communication with PHY (physical layer) device 110 supporting EDC (electronic dispersion compensation), through a 4-pin connection to circuit board 112, on which PHY device 110 is situated.
Advantages provided by the approach illustrated in FIG. 1 are low power dissipation and low latency. Despite those advantages, the drawbacks associated with the conventional approach create substantial roadblocks to widespread LAN implementation of this solution. Those drawbacks include the cost of individual fiber optic cables, which inflate overall costs very rapidly in the LAN environment, where common configurations call for port densities of up to 96 ports per device. In addition, fiber optic cables are susceptible to breakage when heavily manipulated, adding to potential costs and consumption of maintenance resources.
Another conventional approach to supporting 10 GbE communication in LANs is a copper cable solution, shown in FIG. 2. As seen there, networking system 200 includes communication system 208 having connection port 206, in communication with a remote communication system (not shown) through copper cable 202 having connection plug 204. In a typical copper cable solution for 10 GbE, connection plug 204 may be an RJ-45 type connector, for example, connected to an Ethernet port at connection port 206. In this conventional solution, connection port 206 is in communication with PHY device 210 supporting 10 GbE, through circuit board 212, on which PHY device 210 is situated.
Advantages provided by this conventional approach include low cost and the durability of copper cabling when compared to optical cables. Drawbacks associated with conventional copper cable solutions are significant as well, however. Power dissipation, which can vary with cable length, may range as high as 10 Watts for a 100 m copper cable connection. That demand for power may place too low a threshold on the number of ports that may be supported on existing datacenter chassis, resulting either in inefficient use of existing systems, or their costly replacement. Latency is also an issue for 10 GbE over copper cable, where values as high as 2.5 microseconds are seen.
Accordingly, there is a need to overcome the drawbacks and deficiencies in the art by providing network solutions that can offer cost effective, durable, and power sparing alternatives to conventional approaches to supporting 10 GbE.